1. Field of the Invention
The present invention relates to an image capturing optical lens system, and more particularly, to a compact image capturing optical lens system used in electronic products.
2. Description of the Prior Art
In recent years, with the popularity of portable electronic products having photographing function, the demand of compact imaging lens system has grown. Generally, the sensor of a general photographing camera is none other than CCD (Charge Coupled Device) or CMOS device (Complementary Metal Oxide Semiconductor device). Furthermore, advances in semiconductor manufacturing technology have allowed the pixel size of sensors to be reduced and therefore lead compact imaging lens systems to higher resolution. In the meantime, the demand for better image quality is also increased.
A conventional image capturing lens system equipped on a portable electronic product is in various design of two-lens element, three-lens element, four-lens element or five-lens element, such as the one set forth in U.S. Pat. No. 7,365,920. However, with the popularity of high level portable electronic products, such as smart phone and PDA (Personal Digital Assistant), the demand for the pixel size and image quality of compact imaging lens system increase fast, and the conventional lens system with four lens elements can no longer satisfy the imaging lens systems of even higher level. Moreover, a conventional image capturing lens system having five lens elements usually adopts different assemblies of positive or negative refractive power or has a cemented doublet lens element. This kind of five-lens element lens system frequently has the drawback of excessively long total track length so that is not suitable for compact electronic products
Inasmuch as the foregoing, a need is continuously existed for a lens system with good image quality and moderate total track length and is suitable for compact and portable electronic products.